Gripper mechanism



Jan. 18, 1944. W, H, wlsE ET AL l 2,339,310

GRIPPER MECHANISM Filed MaIhlS, 1940 3 Sheets-Sheet 1 Jan. 18, 1944.

W. H. -WISE ET AL GRIPPER MECHANI SM 5 sheets-shea 2 Filed March 18,1940 S R O T N E V m yW. H. WISE ETAL l Jan. 18, 1944.

GRIPPER MECHANISM Filed March 18, 1940 3 Sheets-Sheet 3 Patented Jan.18, 1944 2,339,310 GRIPPER MECHANISM Wiuiam'H. Wise and August A. seul,Pittsburgh, Pa., assignors to Miller Printing Machinery Co., Pittsburgh,Pa., a corporation of Pennsylvania Application March 18, 194i), SerialNo. 324,474 1 l 1o claims. (ci. 1er-409)` Thisrinventionrelates togripper mechanism `for use in connection with printing presses and thelike. vOne of its objects is to improve the operation of grippers inprinting presses and the like and reduce the noise incident to gripperoperation. VA further object of the invention is to provide improvedmeans for urging the grippers into operative position when the grippersare in such position, but which may be rendered comparativelyinoperative when the grippers move to inoperative position.

We `provide gripper mechanism comprising' a gripper, means for movingthe gripper between operative and inoperative positions,4 shiftablemeans connected with the gripper and having movement consonant with themovement of the gripper and vspring pressed means for urging the gripperinto operative position when the gripper is in Asuch position, saidshiftable means and said spring pressed means being so constructed andarranged relatively to each other that movement of the shiftable meansupon movement oi the gripper to inoperative position renders the springpressed4 means comparatively inoperative.

The shiftable means may take the form of cam if means cooperating withthe spring pressed means, the cam means preferably being shaped so thatmovement thereof upon movement of the gripper to inoperative positionrenders the spring pressed means comparatively inoperative. Theshiftable means may take the form of lever means connected. with thegripper and the spring pressed means may have connection with a portionof the lever means so as to urge through the lever means the gripperinto operative position when the gripper is in such position, and thespring pressed means may be disconnected from said portion of the levermeans but may bear against another portion thereof when the gripper isin operative position. Such mechanism insures exceptionally accurate,reliable and quiet operation of the grippers at maximum efficiency andwith the least waste of power.

Other details, objects and advantages of the invention will becomeapparent as the following description of a present preferred embodimentthereof proceeds.

In the accompanying drawings we have shown a present preferredembodiment of the invention, in which Figure 1 is a fragmentary centralvertical longitudinal cross-sectional View through the cylinder of aprinting press showing a portion of ating mechanism;

' Figure Y2 is a verticall transverse cross-section- "al View throughthe cylinder showing'aportion of the gripper operating andcontrol-mechanism;

Figure 3 is a fragmentary vertical transverse cross-sectionalviewthrough the cylinder taken on the line III-III of Figure 1 showinganother portion ofY the gripper operating and control mechanism; YFigure 4 is a fragmentary enlarged vertical transverse 'cross-sectionalView through a portion of the cylinder taken on the line IV-IV of Figure1; l i

Figure 5 is ya fragmentary enlarged vertical transverse cross-sectionalview through a portion oftheoylinder taken on the line V--V of Figure 1;

Figure 6 isa view similar to Figure 4 but showing the parts in adifferent operative position; and

' Figure 7 is a View similar to Figure 5 but showing the parts in adifferent operative position.

lReferring now more particularly to the drawings, the printing pressillustrated is of the Well known flatbedand cylinder type and comprisesopposed side frames one of which is shown fragmentarilyfin Figure 1 anddesignated by referencenumeral 2`, the opposite frame being of generallysimilar construction. Carried by each side frame is the usual bearing(not shown) for receiving one of the cylinder trunnions, as well knownin the art. The press cylinder is designated by reference numeral 5 andhas rigidly connected therewith at its opposite ends trunnions which are.iournaled in said bearings in the side frames. The drive for thecylinder and bed may be conventional.

Mounted in ther-cylinder 5 adjacent the periphery thereof for limitedrotary movement is'a gripper shaft l2 having iixed thereto at intervalstherealong a series of grippers I3. The function of `the grippers |3fisto grip the sheets as they arefregisteredto the press and hold the same,infproperposition on the cylinder during printing `In operation of thepress the cylinder turns in the direction of the arrowAf(counterclockwise) in Figure 2. VThe. press is provided with drop'guides VI4 (Figure 4), which are operated in Y,c'ofnventional manner.As the means for operatingfthe drop guidesldoes not constitute the pres-.ent invention such means isy not shown in'detail. In `operationuof thepress, as a sheet is advanced en th'e usualeed board (not shown) towardthe cylinderjthejdirection` of sheet feed being generallylfromf right.to leftat the top ofthe cylin- Nder; viewing Figure "2) th'e'drop guidesyare lowered into operative position to properly register the sheet. Thefront edge of the sheet strikes the drop guides so that the sheet ispositioned to be seized by the grippers I3. After registering the sheetthe drop guides are raised in usual manner. As the cylinder rotates thegripper shaft I2 is turned quickly in the clockwise direction viewingFigure 2 to seize the registered sheet at the proper instant and holdsuch sheet in place on the cylinder during printing. After the sheet hasbeen printed the grippers are released by turning the gripper shaftI2Vin the counterclockwise direction viewing Figure 4 to allow the sheetto be stripped from the cylinder by conventional strippers I6.

Journaled in the cylinder '5 is a shaft I1 whose axis is parallel to theaxis of the cylinder and to which is xed an arm I8 carrying at itsextremity a gear segment I9 in mesh with a pinion 20 fixed to thegripper shaft I2. Also xed to the shaft I1 outside the end of thecylinder is an arm 2I carrying at its outer end a.cam follower 22 in theform of a rotatable sleeve. The cam follower 22 is adapted to ride incam tracks 23 and 24 formed, respectively, by cams 25 and 26. The camscause periodic turning of the shaft I1 during operation of the press,which turning results in swinging of the arm I8 and, through the segmentI9 and the pinion 29, turning of the gripper shaft I2 to move thegrippers I3 into and out of operative position.

The cam 25 is carried by the press frame 2 and is mounted therein forsliding movement toward and away from the cylinder by pins 21 and 29which are fixed to the cam 25 and which slide in bores in the frame 2.The cam 26 is carried by the press frame 2 and is mounted therein forsliding movement toward and away from the cylinder .5 by pins 29 and 30which are fixed to the cam 26 and which slide in bores in the frame 2.Thus each of the cams and 23 is movable into and out of cooperativerelationship with respect to the cam follower 22 carried b y the arm 2l.The function of the cam 26 is to cause the grippers to move to operativeposition.

The function of the cam 25 is to cause the grippers to move toinoperative position. The cam 26 also performs an additional function inthat if the grippers should be in operative position when the follower22 engages the cam 26 such cam will cause the grippers first to be movedto inoperative position and then to be returned to operative position.Similarly, the cam 25 also performs an additional function in that ifthe grippers should be in inoperative position when the follower 22engages the cam 25 such cam will cause the grippers rst to be moved tooperative position and then to be returned to inoperative position.Means not shown are provided for moving the cams, 25 and 26 axially ofthe pins 21, 28, 29 and 3B to insure against closing of the gripperswhen no sheet is registered to the drop guides. Such means are wellknown to those skilled in the art and constitute no part of the presentinvention. V

Fixed to the vgripper shaft I2 is a cam 3| having a generally radialportion 32. Adjoining the radial portion 32 of the carn at the Outerextremity of such portion is a circular cam portion 33 into closedposition.

tion 33 to the inner end of the radial portion 32 as shown in Figure 5.

Carried by the cylinder is a fixed pin 34 serving as a bearing for alink 35 one end of which is rotatably mounted upon said pin. Pivoted tothe opposite end of the link 35 is a head 36 xedly fastened to a rod 31by a pin 38. At its opposite end the rod 31 is slidably received withina socket 39 having a bearing edge 40 bearing in a notch 4I in a bar 42forming part of the cylinder 5. Surrounding the rod 31 and bearingagainst an annular projection 43 on the head 36 is a coil spring 44 theopposite end of which bears against a shoulder 45 on the socket 39. Thusthe spring in effect presses between a fixed portion of the cylinder andthe head 35. The head 35 is pivoted to the link 35 by a pin 46, whichpin also carries a roller 41 positioned to engage the cam 3l.

.When the grippers I3 are in inoperative or open position the roller 41rides on the circular portion 33 of the cam 3|, as shown in Figure '1.When the parts are in such position the reaction of the roller 41 on thecam is directed generally radially of the cam so that the spring 44 hasno tendency to urge the gripper shaft I2 in either direction. There is aslight tendency to hold the gripper shaft in xed position due to thefriction between the roller 41 and the cam 3I.

When the gripper shaft is turned to move the grippers into operativeposition the roller 41 rides from the circular portion 33 of the cam 3Ito the radial portion 32 thereof, passing from the portion 33 to theportion 32 just as the grippers snap to operative or closed position.Figure 5 shows the position of the parts when the grippers are closed.In such position-the force of the spring 44 is directed fully againstthe radial portion 32 of the cam 3|, thus firmly pressing the grippersAs the gripper shaft is turned to open the grippers in a subsequentoperation the roller 41 rides from the radial portion 32 of the cam ontothe circular portion 33 when it becomes relatively inoperative to urgethe gripper shaft in either direction of rotation.

Fixed to the gripper shaft I2 is a lug 48 forming a toggle memberthrough which the gripper shaft may be urged toward either of itsextreme positions after it passes center. Pivoted to the toggle lug 43lby a pin 49 is a head 50 fixed on a rod 5I. At its opposite end the rod5I is mounted on the cylinder 5 similarly to the mounting of the lowerend of the rod 31 as shown in Figure 2. Surrounding the rod 5i andbearing against an annular projection 56 on the head 59 is a coil spring51 the opposite end of which is backed by a portion of the cylinder.Thus the spring in effect bears between a portion of the cylinder andthe head which is pivoted to the toggle lug 48. As the gripper shaft I2moves from one position to the other the toggle lug 49 passes center sothat the toggle spiing 51 is effective in either position of the grippershaft for urging such shaft toward its extreme position. The togglespring 51 is of less strength than the spring 44, the function of thetoggle spring being simply to insure that the gripper shaft I2cornpletes its movement in each direction. The spring 44 supplies theforce mainly relied upon to urge the grippers firmly into operativeposition to hold the sheets on the cylinder.

While we have shown and described a present preferred embodiment of theinvention it is to be distinctly understood that the invention is notlimited thereto but may be otherwise variously embodied within the scopeof the following claims.

We claim:

1. Gripper mechanism comprising a gripper, means for moving the gripperbetween operative and inoperative positions, cam means connected withthe gripper and having movement consonant with the movement of thegripper and spring pressed means for urging the gripper into operativeposition when the gripper is in such position, said cam means and saidspring pressed means being so constructed and arranged relatively toeach other that movement of the cam means upon movement of the gripper.to inoperative position renders the spring pressed means comparativelyinoperative.

2. Gripper mechanism comprising a gripper, means for moving the gripperbetween operative and inoperative positions, cam means connected withthe gripper and having movement consonant with the movement of thegripper and spring pressed means bearing against the cam means andthrough the cam means urging the gripper into operative position whenthe gripper is in such position, the cam means being shaped so thatmovement thereof uponY movement of the gripper to inoperative positionrenders the spring pressed means comparatively inoperative.

3. Gripper mechanism comprising a gripper, means for moving the gripperbetween operative and inoperative positions, lever means connected withthe gripper and having movement consonant with the movement of thegripper and spring pressed means having connection with a portion of thelever means so as to urge through the lever means the gripper intooperative position when the gripper is in such position and disconnectedfrom said portion of the lever means but bearing against another portionthereof when the gripper is in inoperative position.

4. Gripper mechanism comprising a gripper, means for moving the gripperbetween operative and inoperative positions, means having an abutmentconnected with the gripper and having movement consonant with themovement of the gripper and spring pressed means bearing against saidabutment when the gripper is in operative position to urge through saidsecond mentioned means the gripper into operative position, said secondmentioned means moving upon movement of the gripper out of operativeposition so as to break contact between said spring pressed means andsaid abutment.

5. Gripper mechanism comprising a gripper, means for moving the gripperbetween operative and inoperative positions, cam means connected withthe gripper and having movement consonant with the movement of thegripper, the cam means having an abutment portion, and spring pressedmeans bearing against said abutment portion and through the cam meansurging the gripper into operative position when the gripper is in suchposition, the cam means moving upon movement of the gripper out ofoperative position so as to separate the spring pressed means from theabutment portion.

6. Gripper mechanism comprising a gripper, means for moving the gripperbetween operative and inoperative positions, cam means connected withthe gripper and having movement consonant with the movement of thegripper, the cam means having an abutment portion, and spring pressedmeans bearing at all times against the cam means and'when the gripper isin operative position bearing against said abutment portion wherebythrough the cam means to urge the gripper into said position, the cammeans acting upon movement of the gripper out of operative position tocam the spring pressed means away from said abutment portion.

'7. Gripper mechanism comprising a gripper, means for moving the gripperbetween operative and inoperative positions, cam means connected withthe gripper and having movement consonant with the movement of thegripper, the cam means having an abutment portion, a pivot, -a linkhaving one end carried by said pivot, a follower carried by said linkand at all times urged against the cam means, the follower bearingagainst said abutment portion and through the cam means urging thegripper' into operative position when the gripper is in such position,the cam means moving upon movement of the gripper out of operativeposition so as to separate the follower from the abutment portion.

8. Gripper mechanism comprising a gripper, means for moving the gripperbetween operative and inoperative positions, cam means connected withthe gripper and having movement consonant with the movement of thegripper, the cam means having an abutment portion, a pivot, a linkhaving one end carried by said pivot, a spring pressed rod pivoted tothe other end of the link, said second mentioned end of the link havingmeans bearing at all times against the cam means and when the gripper isin operative position bearing against said abutment portion wherebythrough the cam means to urge the gripper into said position, the-cammeans acting upon movement of the gripper out of operative position tocam said means on the second mentioned end of the link away from saidabutment portion.

9. Gripper mechanism comprising a gripper, means for moving the gripperbetween operative and inoperative positions, cam means connected withthe gripper and having movement consonant with the movement of thegripper, the cam means having an abutment portion, spring pressed meansbearing at al1 times against the cam means and when the gripper is inoperative position bearing against said abutment, portion wherebythrough the cam means to urge the gripper into said position, saidspring pressed means when the gripper is in inoperative position bearmgagainst a portion of the cam means so as to have comparatively little,if any, effect upon the gTlppel- 10. Gripper mechanism comprising agripper, means for moving the gripper between operative and inoperativepositions, cam means connected with the gripper and having movementconsonant with the movement of the gripper and spring pressed meansengaging the cam means, the cam means being so constructed and arrangedthat as the gripper moves into operative position the spring pressedmeans will bear upon a portion thereof causing the gripper through thecam means to be pressed into operative position.

WILLIAM H. WISE. AUGUST A. SAUL.

